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J Rosenman

Publications and source records attributed to J Rosenman.

At least 37 records · Page 2Linked to original sources
PubMed1993

Future directions in 3-dimensional radiation treatment planning.

In recent years, computed tomography data have been used to build three-dimensional (3D) patient models for radiation treatment planning. The strength of 3D treatment planning systems lies in their ability to substantially improve the precision of radiation therapy and provide some of the tools needed to improve dose conformation. This article describes the V2 virtual simulation system used at the University of North Carolina at Chapel Hill. The virtual simulator allows the patient model to be rotated to determine the best beam angles and calculates the positions of the table, gantry, and collimator necessary to achieve desired beam orientations. Considerable disagreement remains as to how to produce an optimal radiation treatment plan using 3D systems. The University of North Carolina's VISTAnet project provides real-time 3D radiation dose calculation and display, allowing the user to search for the optimal plan.

Humans↗
PubMed1992

An electronic medical record system with direct data-entry and research capabilities.

The transfer of medical records from a paper system to a computer-based system is inevitable. However, the widespread acceptance of electronic medical records has been delayed by problems such as high cost, inefficiency, data entry errors and poor physician acceptance. We have developed a database system that has overcome these difficulties and now serves as an electronic medical record. Our system has been in use for a year and a half, and currently contains information on over two thousand patients. The database provides an electronic radiation oncology chart containing patients' demographic information, technical treatment data and dictated reports. All dictated notes are captured, including consultation notes, treatment summaries, on-treatment visits, letters and follow up reports. The system provides data validation upon entry, required few additional software or hardware purchases, and allows for efficient retrieval of data. Unlike other database systems which require the hiring of data entry clerks to input the data, ours combines transcription and data entry. The database runs on a local area network of computers and uses a commercially available relational database package. It makes extensive use of mouse interface features such as pull-down menus, pop-up lists, buttons, multi-page forms, and scrolling fields, making the system easy to use with minimal training. Many custom features are built in, such as help screens, control functions, audit trails, and a system that keeps track of each patient's referring and other relevant physicians. For research purposes, the system has the capability to perform survival analyses on arbitrary user-defined subsets of patients. Data may also be exported transparently to statistical packages for other types of analyses.

Data Display↗
PubMed1992

High-performance computing in radiation cancer treatment.

In 1989 a consortium of the Radiation Oncology and Computer Science Departments at the University of North Carolina, BellSouth Corporation, GTE, and the MCNC was formed in response to the high-speed network initiative proposed by the National Science Foundation and the Defense Advanced Research Projects Agency. One of the purposes of this effort has been to demonstrate that applications exist that require gigabit per second networks. Our consortium, known as VISTAnet, proposed to use real-time radiation therapy treatment planning as the application that would require the use of a gigabit network. The plan was to develop a system that could rapidly calculate and display a three-dimensional radiation dose distribution for any configuration of radiation beams. The gigabit network would be used to tie the dose calculations done with the Cray Y-MP at the Research Triangle to the graphics engine at the Department of Computer Science (Pixel-Planes 5) and the medical workstation at Radiation Oncology. The system would then provide the radiation physician with the capability of considering hundreds of potential treatment plans, instead of the usual two or three, with the goal of arriving at a highly optimized plan within a few minutes.

Computer Communication Networks↗
PubMed1992

Penetrating thoracic wounds caused by plastic bullets.

Thoracic penetrating injuries caused by a new plastic bullet were studied to determine the nature of the wounds and the appropriate management. Twenty-six casualties from the Israeli-Palestinian conflict (Intifada) were included. The organs most commonly involved were lung (n = 21), bony chest wall (n = 9), heart (n = 3), and diaphragm. Bleeding was at least moderate in 20 patients, amounting in all patients to an average of 975 ml. Thoracotomy was required in 11 patients (42%) mainly because of cardiac injury (n = 3) and aortic or other arterial bleeding (n = 3). Simple oversewing of severed organs (n = 8) or ligation of bleeding vessels (n = 3) was satisfactory. Two patients died (7.7% mortality); one after major liver resection; the other was dead on arrival. We conclude that plastic bullets have a linear course unless displaced by the bony chest wall, when they tend to fragment and cause simple fractures. Fired from a presumed range of at least 70 m, plastic bullets behave like low-velocity missiles, and tissue destruction is minimal. Management should be similar to that of civilian thoracic penetrating trauma.

Adolescent↗
PubMed1991

Virtual simulation: initial clinical results.

We have developed a graphics-based three-dimensional treatment design system that permits the physician to easily understand which anatomy will be treated for any arbitrary beam orientation. Our implementation of this system differs from others in that the software (the Virtual Simulator) simulates the full functionality of a (physical) radiation therapy simulator allowing it to be easily used by physicians. The details of the of our initial clinical experience with virtual simulation are presented in this paper. Virtual simulation was attempted in 71 patients and completed in 65. In 41/71 patients (58%), the beam orientations chosen differed significantly from those traditionally used in our department. Although virtual simulation lead to traditional radiation portals in the remaining patients, in 23/71 (32%) secondary blocking was designed which was different from that which would have been conventionally employed. Thus, overall, virtual simulation lead to treatment changes in 64/71 (90%) of the patients in whom it was attempted. In 78% of evaluable patients the treatment designed with virtual simulation could be implemented on the physical simulator with a precision of +/- 5 mm (+/- 3 mm for brain and head and neck). Thus virtual simulation allowed both accurate planning and execution of treatment plans that would be difficult to achieve with conventional methods.

Brain Neoplasms↗
PubMed1991

Recent advances in radiotherapy treatment planning.

Radiation treatment planning is currently in a state of rapid change. Dissatisfaction with past planning technology stems from the growing realization that: (1) Increases in the local regional tumor control rate will increase the cure rate in many malignancies. (2) Even at the best treatment centers geometric tumor misses are commonplace. (3) Traditional constraints on treatment techniques, originally imposed for simplicity and reproducibility, are no longer necessary, and can result in suboptimal treatment. (4) Treatment plans judged "optimal" in two dimensions may be far from optimal when viewed over the entire treatment volume. (5) Lack of treatment reproducibility is also commonplace, and can be demonstrated to adversely affect treatment outcome. On the positive side, recent developments in computer graphics, image processing, radiation physics, and radiation biology are now making it possible to define, design, and deliver sophisticated 3D radiation treatments. However, because many of these technologies are being developed for other disciplines, their applicability to radiation therapy treatment planning is not widely appreciated. We outline the current status and new developments in radiation therapy treatment planning.

Artificial Intelligence↗
PubMed1989

Three-dimensional display techniques in radiation therapy treatment planning.

Good radiation treatment planning requires that the target volume be treated with a high and uniform dose of radiation while irradiating normal tissue as little as possible. Even if the merits of a given treatment plan are judged only on the appearance of isodose lines in one or a few planes it can sometimes be difficult for the experienced radiation oncologist to select the best of several alternative plans. If consideration is given to the entire spatial distribution of dose, however, the problem becomes far more difficult because of the enormous amount of data that must be evaluated. We believe that the lack of suitable methods to display these data has greatly contributed to the slow incorporation of 3D considerations into routine radiation treatment planning. In the past few years there have been great advances in both the theory of how to produce effective 3D displays and in the display hardware itself. In this paper we survey some of the methods used at the University of North Carolina, and show specific examples of how these displays can be used in radiation therapy treatment planning.

Computer Graphics↗
PubMed1989

The predictive value of progesterone receptor levels in endometrial cancer.

Recent reports have suggested that the presence of progesterone receptor correlates with other well known predictors of a favorable outcome for endometrial cancer patients. To test this hypothesis, we reviewed the records of 154 patients who had undergone a hysterectomy for adenocarcinoma of the endometrium, and pelvic irradiation if poor prognostic factors were present. The 3 year disease-free survival for all clinical Stage I patients was 80%. Patients with progesterone receptor levels greater than or equal to 100 had a 3 year disease-free survival of 93% compared with only a 36% 3 year disease-free survival for patients with progesterone receptor less than 100 (p less than .0001, log rank test). To determine whether elevated progesterone receptor was an independent prognostic factor for disease-free survival in endometrial cancer, or just correlated with the other well-known predictors, bivariate and multivariate analyses were conducted. Our results indicate the progesterone receptor levels are the single most important prognostic indicator of 3 year disease-free survival in clinical Stage I endometrial cancer, with only cervical involvement and peritoneal cytology being significant prognostic variables after adjusting for progesterone receptor levels.

Analysis of Variance↗
PubMed1988

Intraperitoneal chromic phosphate therapy after second-look laparotomy for ovarian cancer.

Between 1973 and 1985, 118 patients in clinical remission after initial surgery and postoperative chemotherapy for epithelial ovarian carcinoma underwent second-look laparotomy at the University of North Carolina. No evidence of disease (NED) was found in 57 of these patients; 43 patients received 15 mCi of radioactive chromic phosphate (32P) suspension given intraperitoneally in the immediate postoperative period. In 29 other patients, only microscopic or minimal residual disease (nodules less than 2 cm in size) was found, seven received 32P alone, ten received 32P and further chemotherapy, and 12 received chemotherapy alone. The 4-year postsecond-look survival of the patients with NED at second-look was 89% for those receiving 32P and 67% for those who had not. The respective figures for patients with minimal residual disease at second-look are 59% versus 22%. Irrespective of treatment, a group at high risk for failure after negative second-look laparotomy has been identified; those with an initial International Federation of Gynecology and Obstetrics (FIGO) stage greater than I and histologic grade greater than 1. A comparison of our data with 18 previously published series, indicates that use of postsecond-look intraperitoneal 32P can improve the progression-free interval, and possibly overall survival, of patients with NED or minimal residual disease without adding significant complications.

Carcinoma↗
PubMed1988

The role of computed tomography in the evaluation of post-mastectomy locally recurrent breast cancer.

The rate of post mastectomy local-regional recurrence of breast cancer has remained in the range of 10-30% for decades. The traditional treatment, external beam radiation therapy, is successful in eradicating local disease in most cases, but re-recurrences are seen in about 50% of patients. Since 1982, 33 patients with such recurrences have undergone evaluation with computed tomography (CT) at our institution as part of their diagnostic work-up. In 22/33 (67%), CT revealed unsuspected disease, and in 10 of these patients the radiation treatment plan had to be altered. These results, similar to three other published series, strongly suggest that CT is a necessary part of the work-up of patients with post-mastectomy local-regional recurrences. The significance of these findings with respect to the cause of post mastectomy local-regional failures is further discussed.

Breast Neoplasms↗
PubMed1988

Peritoneal fluid cytology in endometrial cancer: its significance and the role of chromic phosphate (32P) therapy.

Between 1978 and 1986, 243 patients (all stages) had peritoneal fluid cytology performed while undergoing total abdominal hysterectomy for endometrial carcinoma; 39 (16%) were found to be positive. At 3 years (median follow-up of 30 months) the disease-free survival (DFS) for the 165 negative cytology clinical Stage I patients was 91% compared to only 56% for the 25 positive cytology patients (p less than .001). Of the 25 Stage I positive cytology patients, 14 with greater than one-third myometrial invasion had a DFS of 30% at 3 years as compared to 87% for negative cytology patients with comparable depth of invasion (p less than .001). There was no difference in DFS between the negative and positive cytology Stage I patients who had one-third or less myometrial invasion. Stage I patients with histologic Grade 2 and 3 had a lower 3 year DFS when cytology positive, 49% and 22%, versus 92% and 79% when cytology negative (p less than .001 and p = .03 respectively). In clinical Stage II patients the 3-year DFS was 21% for those with a positive cytology and 59% with a negative cytology. Fourteen of the 25 clinical Stage I positive cytology patients received 15 mCi of intraperitoneal 32P. At 3 years they had a 68% DFS as compared to 27% for those not receiving 32P (p = 0.01). All 11 patients with superficial myometrial invasion (9 received 32P) remained disease-free. The 4 Stage I patients with deep invasion who received 32P therapy had an improvement in abdominal/pelvic control and DFS when compared to 9 similar patients who did not receive 32P (p = .02). For histologic Grade 2 and 3 patients, there was a 64% 3-year DFS in the 32P treated group and 16% for those not receiving 32P (p = 0.02). Although 32P therapy improved DFS in Stage I positive cytology patients its use along with pelvic radiation therapy can lead to complications. Of 9 Stage I patients receiving 32P as well as pelvic irradiation, 4 experienced serious bowel complications requiring surgery. None of the 5 patients receiving 32P only had a complication.

Ascitic Fluid↗
PubMed1988

Bronchoscopic evaluation of peripheral lung tumours.

The results obtained from fibreoptic bronchoscopy preformed under fluoroscopic guidance were evaluated in a prospective study of 71 consecutive patients with a peripheral lung lesion more than 2 cm in diameter on the chest radiograph. A peripheral lung lesion was defined as a lesion that was not seen within the bronchial tree at fibreoptic bronchoscopy. Small volume washings, bronchoalveolar lavage, transbronchial biopsy, and bronchial brushings were carried out and fluid or tissue was sent for cytological or histological examination as appropriate. Of the 71 patients, 51 were subsequently shown to have malignant disease. In 38 of the patients the diagnosis of malignancy was made by bronchoscopy, from histological specimens alone or in conjunction with cytological specimens in 33, from brushings alone in two, and from bronchoalveolar lavage fluid alone in three patients. There were no important complications. Thus fibreoptic bronchoscopy in conjunction with fluoroscopic screening appears to be an effective and safe method for the initial investigation of a peripheral lung lesion more than 2 cm in diameter.

Adult↗
PubMed1987

A spreadsheet program for brachytherapy planning.

A computer program (brachy-spread) which allows spreadsheet-like interactive adjustment of the loading of any brachytherapy application has been implemented. Sources are collected into objects, each assigned an activity and duration of implant. Activities and times may be adjusted by moving a cursor to the datum to be edited and entering a new value from the keyboard. Alternatively, the desired total dose to a given calculation point may be edited resulting in a recalculation of the time for all objects. For each of a set of calculation points, dose rates, total doses, and the percent contribution of each object to the point are displayed and instantly updated as the times and activities are adjusted. The program design includes rapidly updated display of isodose curves in previously selected arbitrary planes. A strategy for providing rapid dose display involving precalculation of fractional dose tables is used. The program has significantly reduced the time required to determine the appropriate loading of GYN applications and of implants which involve a combination of line sources and seeds.

Algorithms↗
PubMed1987

Primary radiation therapy for medically inoperable patients with endometrial carcinoma--stages I-II.

Surgery with or without adjuvant radiation is the established method of treating patients with Stage I and II adenocarcinoma of the endometrium. However, patients who are poor operative risks must be treated with radiation therapy only. We report on 73 such patients treated at the University of North Carolina between 1969 and 1980. All patients had an adenocarcinoma of the endometrium; 41 were FIGO Stage I, 32 Stage II. The minimum follow-up period was 4 years. Life table analysis shows a disease-free survival of 72% at 3 years and 57% at 5 years for Stage I patients. There was a strong correlation between histologic tumor grade and survival in these patients; the 5-year survival for grade 1 was 72%, for grade 2 59%, and for grade 3 31%. The difference between G1 and G3 is significant at the p = .045 level. Coexisting medical conditions were responsible for 12 deaths; almost as many as the 16 cancer-related deaths. Stage II patients have an actuarial disease-free survival of 36% at 3 years and 26% at 5 years, significantly worse than Stage I patients (p = .029 at 3 years). Failures were seen in 16/41 (39%) Stage I and 19/32 (59%) Stage II patients; 29/35 (83%) of these recurrences had component of local/pelvic failure and 15/35 (43%) of the recurrences were local/pelvic only. Specific suggestions on how to improve local therapy for these patients are presented.

Actuarial Analysis↗
PubMed1987

Automatic digital contrast enhancement of radiotherapy films.

The practice of radiotherapy involves the precise geometric localization of both anatomic and non-anatomic structures using radiographs which are typically of very low contrast. Portal and verification films suffer from poor contrast as a result of the dominance of Compton interactions at therapeutic energies, and implant localization films often are degraded by extreme patient thickness (lateral pelvis) or projection of bony structures (head and neck). Automatic contrast enhancement techniques developed and proven for optimization of the display of digitally produced images such as CT have been applied to radiotherapy films to improve contrast and augment readability. This approach has become viable only recently with the advent of high speed, high resolution film digitizers and laser cameras and the evolution of sufficiently powerful computer hardware.

Brachytherapy↗